<template>
  <div class="cart">
    <h4>全部商品</h4>
    <div class="cart-main">
      <div class="cart-th">
        <div class="cart-th1">全部</div>
        <div class="cart-th2">商品</div>
        <div class="cart-th3">单价（元）</div>
        <div class="cart-th4">数量</div>
        <div class="cart-th5">小计（元）</div>
        <div class="cart-th6">操作</div>
      </div>
      <div class="cart-body">
        <ul class="cart-list" v-for="(cart,index) in cartInfoList" :key="cart.id">
          <li class="cart-list-con1">
            <!--checkbox有一个checked属性-->
            <input type="checkbox" name="chk_list" :checked="cart.isChecked===1"
                   @click="chooseOne(cart)">
          </li>
          <li class="cart-list-con2">
            <img :src="cart.imgUrl">
            <div class="item-msg">{{ cart.skuName }}</div>
          </li>
          <li class="cart-list-con4">
            <span class="price">{{ cart.skuPrice }}.00</span>
          </li>
          <li class="cart-list-con5">
            <a class="mins" @click="updateSkuNum(cart,'reduce')" style="cursor: pointer">-</a>
            <input autocomplete="off" type="text" :value="cart.skuNum" class="itxt"
                   @change="updateSkuNum(cart,'input')">
            <a class="plus" @click="updateSkuNum(cart,'add')" style="cursor: pointer">+</a>
          </li>
          <!--小计-->
          <li class="cart-list-con6">
            <span class="sum">{{ cart.skuPrice * cart.skuNum }}</span>
          </li>
          <li class="cart-list-con7">
            <a class="sindelet" @click="deleteCart(cart)" style="cursor: pointer;">删除</a>
            <br>
            <a href="#none">移到收藏</a>
          </li>
        </ul>
      </div>
      <div v-show="JSON.stringify(cartList)==='{}'" style="text-align: center">
        <h3>你的购物车为空哦</h3>
      </div>
    </div>
    <div class="cart-tool" v-show="JSON.stringify(cartList)!=='{}'">
      <div class="select-all">
        <input class="chooseAll" type="checkbox" @click="chooseAll()" :checked="isAllChecked()">
        <span>全选</span>
      </div>
      <div class="option">
        <a href="#none" @click="delChooseSku">删除选中的商品</a>
        <a href="#none">移到我的关注</a>
        <a href="#none">清除下柜商品</a>
      </div>
      <div class="money-box">
        <div class="chosed">已选择
          <span>{{chooseNUm}}</span>件商品
        </div>
        <div class="sumprice">
          <em>总价（不含运费） ：</em>
          <i class="summoney">{{ sum }}</i>
        </div>
        <div class="sumbtn">
          <router-link class="sum-btn" to="/trade" >结算</router-link>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import {mapGetters} from "vuex";
import {reqAddOrUpdateShopCart, reqCheckCart, reqDeleteCart} from "@/api";
// 引入lodash的节流函数js文件
import throttle from 'lodash/throttle'

export default {
  name: 'ShopCart',
  mounted() {
    this.getData();
  },
  methods: {
    getData() {
      // 妹妹是笨蛋～
      this.$store.dispatch('getShopCart')
    },

    // 全选复选框点击事件
    chooseAll() {
      this.cartInfoList.forEach(async item => {
        item.isChecked === 1 ? item.isChecked = 0 : item.isChecked = 1;
        // 发送请求更改商品状态
        const result = await reqCheckCart(item.skuId, item.isChecked);
        if (result.code !== 200) {
          alert('更改商品状态失败')
        }
      })
    },

    // 商品单选复选框点击事件
    async chooseOne(cart) {
      cart.isChecked === 1 ? cart.isChecked = 0 : cart.isChecked = 1;
      // 发送请求更改商品状态
      const result = await reqCheckCart(cart.skuId, cart.isChecked);
      if (result.code !== 200) {
        alert('更改商品状态失败')
      }
    },

    // 全选复选框是否选中状态
    isAllChecked() {
      // 数组的every方法：只要数组里的每一项都满足条件返回ture，否则false
      return this.cartInfoList.every(item => item.isChecked === 1)
    },

    // 修改购物车商品的数量(throttle节流)
    updateSkuNum: throttle(async function (cart, type) {
      let skuNum;
      if (type === 'reduce') {
        // 商品数量大于1才能给服务器带-1，否则带0
        skuNum = cart.skuNum > 1 ? skuNum = -1 : skuNum = 0
      } else if (type === 'add') {
        // 增加购物车商品的数量
        cart.skuNum++;
        skuNum = 1
      } else {
        // input修改购物车商品的数量
        const value = event.target.value * 1;
        // 不能输入非数字切小于1的
        if (isNaN(value) || value < 1) {
          skuNum = 0
        } else {
          // 不能输入小数
          skuNum = parseInt(value) - cart.skuNum
        }
      }
      // 向服务器发送请求，更新商品的数量
      const result = await reqAddOrUpdateShopCart(cart.skuId, skuNum);
      if (result.code === 200) {
        this.getData()
      } else {
        alert('修改商品数量失败')
      }
    }, 5),

    // 删除购物车商品
    deleteCart(cart) {
      if (confirm(`确定要删除商品名称为${cart.skuName}的商品吗？`)) {
        this.delSkuById(cart.skuId)
      }
    },

    // 删除商品方法
    async delSkuById(skuId) {
      const result = await reqDeleteCart(skuId);
      if (result.code !== 200) {
        alert('删除失败')
        return
      }
      // 更新购物车的数据
      this.getData()
    },

    // 删除选中的商品
    delChooseSku() {
      const skuIdArr = [];// 存放商品id的数组
      this.cartInfoList.forEach((item) => {
        if (item.isChecked === 1) {
          skuIdArr.push(item.skuId)
        }
      })

      if (skuIdArr.length === 0) {
        // 没有选中的商品
        return alert('请选中要删除的商品')
      } else {
        if (confirm(`确定要删除选中的商品吗？`)) {
          skuIdArr.forEach(skuId => {
            this.delSkuById(skuId)
          })
        }
      }
    }
  },
  computed: {
    ...mapGetters(['cartList']),
    // 购物车信息列表
    cartInfoList() {
      return this.cartList.cartInfoList || []
    },

    // 计算购物车的总价
    sum() {
      let sum = 0;
      this.cartInfoList.forEach(item => {
        sum += item.skuPrice * item.skuNum
      })
      return sum
    },

    // 计算选择了多少商品
    chooseNUm(){
      let count=0
      this.cartInfoList.forEach(item=>{
        if (item.isChecked===1){
          count++
        }
      })
      return count
    }

  }
}
</script>

<style lang="less" scoped>
.cart {
  width: 1200px;
  margin: 0 auto;

  h4 {
    margin: 9px 0;
    font-size: 14px;
    line-height: 21px;
  }

  .cart-main {
    .cart-th {
      background: #f5f5f5;
      border: 1px solid #ddd;
      padding: 10px;
      overflow: hidden;

      & > div {
        float: left;
      }

      .cart-th1 {
        width: 25%;

        input {
          vertical-align: middle;
        }

        span {
          vertical-align: middle;
        }
      }

      .cart-th2 {
        width: 25%;
      }

      .cart-th3,
      .cart-th4,
      .cart-th5,
      .cart-th6 {
        width: 12.5%;

      }
    }

    .cart-body {
      margin: 15px 0;
      border: 1px solid #ddd;

      .cart-list {
        padding: 10px;
        border-bottom: 1px solid #ddd;
        overflow: hidden;

        & > li {
          float: left;
        }

        .cart-list-con1 {
          width: 15%;
        }

        .cart-list-con2 {
          width: 35%;

          img {
            width: 82px;
            height: 82px;
            float: left;
          }

          .item-msg {
            float: left;
            width: 150px;
            margin: 0 10px;
            line-height: 18px;
          }
        }

        .cart-list-con4 {
          width: 10%;

        }

        .cart-list-con5 {
          width: 17%;

          .mins {
            border: 1px solid #ddd;
            border-right: 0;
            float: left;
            color: #666;
            width: 6px;
            text-align: center;
            padding: 8px;
          }

          input {
            border: 1px solid #ddd;
            width: 40px;
            height: 33px;
            float: left;
            text-align: center;
            font-size: 14px;
          }

          .plus {
            border: 1px solid #ddd;
            border-left: 0;
            float: left;
            color: #666;
            width: 6px;
            text-align: center;
            padding: 8px;
          }
        }

        .cart-list-con6 {
          width: 10%;

          .sum {
            font-size: 16px;
          }
        }

        .cart-list-con7 {
          width: 13%;

          a {
            color: #666;
          }
        }
      }
    }
  }

  .cart-tool {
    overflow: hidden;
    border: 1px solid #ddd;

    .select-all {
      padding: 10px;
      overflow: hidden;
      float: left;

      span {
        vertical-align: middle;
      }

      input {
        vertical-align: middle;
      }
    }

    .option {
      padding: 10px;
      overflow: hidden;
      float: left;

      a {
        float: left;
        padding: 0 10px;
        color: #666;
      }
    }

    .money-box {
      float: right;

      .chosed {
        line-height: 26px;
        float: left;
        padding: 0 10px;
      }

      .sumprice {
        width: 200px;
        line-height: 22px;
        float: left;
        padding: 0 10px;

        .summoney {
          color: #c81623;
          font-size: 16px;
        }
      }

      .sumbtn {
        float: right;

        a {
          display: block;
          position: relative;
          width: 96px;
          height: 52px;
          line-height: 52px;
          color: #fff;
          text-align: center;
          font-size: 18px;
          font-family: "Microsoft YaHei";
          background: #e1251b;
          overflow: hidden;
        }
      }
    }
  }
}
</style>